Low Protein Days: Fight protein habituation, improve cell health and performance

Low Protein Days

Fight protein habituation, improve cell health and performance

Written by Joachim Bartoll, April 17, 2016
Classic Muscle Newsletter #19, 2016


In my second book, ‘The Maximum Muscle Guide,’ published in mid-2009, I wrote a chapter on protein cycling. The main reason for including “low protein days” (less than 50 g protein during 24 hours), was to avoid protein habituation. At the time of writing the book, I had used the concept of restricting protein to less than 50 grams one day every 7 to 14 days since the late 90’s. It simply made sense since we consume huge amounts of protein pretty much year-round – both when gaining muscle mass and when cutting body fat. We already knew that an increase in protein intake did lead to greater protein synthesis over the short term. However, I theorized that if the levels are always kept super high, the body adapts to that intake by increasing protein oxidation (basically wasting protein as fuel). So over time, as you consume a ton of protein on a constant basis you will build a habituation to the protein and it will lose its muscle-building properties. During the 2000’s, several studies confirmed this theory, and low protein days was included in the ‘The Maximum Muscle Guide’ as a strategy to build muscle more efficiently.

Since I wrote ‘The Maximum Muscle Guide,’ a lot of coaches and people within the industry have copied my idea and several variants of low protein days and low protein fasting has been researched within the antiaging community. And one common denominator in recent research is autophagy. Autophagy is your body’s natural cleaning process, which recycles the “junk” in your cells and turns it into energy. This is the cellular equivalent of a spring cleaning or burning your trash to stay warm. You see, over time cells accumulate dead organelles, damaged proteins, and oxidized particles that interfere with cell function (especially the mitochondria) and accelerate aging. Autophagy is the body’s method of ridding itself of this clutter, meaning it helps to keep you healthy, young, and mentally sharp. In other words, autophagy is something you want your cells to do as well as possible in order to look, feel, and perform your best on a daily basis.

Another interesting fact about autophagy is that it plays an important role in maintain muscle mass, and it actually inhibits muscle breakdown for a short period of time in adults.

Most of us know that fasting helps the body to get rid of junk, and part of the reason is that fasting is one of the main signals for the body to turn on autophagy. However, in recent years, researchers have found an even stronger signal to turn on autophagy, and that is by occasionally limiting protein consumption. When you do this, you force your cells to find every possible way to recycle proteins. During this process, they will bind and excrete toxins that were lurking in your cell’s cytoplasm, the gel-like substance enclosed within the cell membrane. It’s like taking something apart and clean every part of it before you put it together again instead of just wiping it off with a cloth – as you would do when cleaning a gun for example. It’s deep cleaning at a cellular level.

Now, being temporarily protein deficient will lower insulin production and mTOR activity. You might ask why a constrained mTOR activity would be desirable, considering that mTOR is the signal or muscle growth. By stomping down mTOR for a limited amount of time, it will spring back up at record levels once you eat enough protein again. While being chronically protein deficient (as seen in many vegans and vegetarians) is awful for your brain and your body, being protein deficient for only 24 to 28 hours will accomplish the exact opposite.

The most obvious way to accomplish this is by doing a traditional 24 to 36 hours fast once a week. However, this can be inconvenient if you have a job, a family or enjoy hanging out with your friends. Another problem, depending on your current physiology and amount of muscle mass, is performance loss the day after the fast. So, if you don’t like the idea of fasting for a minimum of 24 hours, another approach is intermittent fasting with a very low protein intake. This is the approach I have used with most of my clients for the last 10 years.

For simply avoiding protein habituation, protein intake should be limited to 40 to 60 grams depending on your amount of muscle mass and body weight. If you consume the protein in the evening after fasting for at least 16 hours, you’ll get some good autophagy activation. Still, the window will be limited to only about 16 hours. It’s like hiring a professional cleaning crew for you house only to send them home while there are still rooms left to clean. So, how can we improve this?

Simple, by consuming even less protein. Ideally, you’ll only eat fats and a moderate amount of carbohydrates when breaking the fast. Since most carbohydrate sources, and even vegetables, contain some amount of protein, you will probably still get 10 to 20 grams of low-quality protein. The trick here is to split the meals into at least two, preferable three. By doing this and only focusing on fats and some carbohydrates, there should not be enough leucine in one meal to stimulate protein synthesis and mTOR.
Considering that the protein found in plant-based food have an inferior amino acid profile and that the body only can absorb about 60 to 70 percent of the protein from these foods because of fiber and antinutrients, you should be safe even if you eat several servings of rice, potatoes or even bread. Still, aiming for a maximum of 15 grams of protein during a feeding window of 6 to 8 hours would be ideal. By doing this, autophagy will remain somewhat activated even after you have eaten and until you break your fast the next day with consuming some protein (and you should, because extended autophagy will lead to loss of muscle mass). Doing it this way will probably land you in the neighborhood of 30 hours – and the calories you consumed will help against cortisol and the fats will help in hormone production. It’s a win-win.

If you’re not fond of intermittent fasting, there is still hope. The first thing you need to do is to focus on small meals of only fats during the day and a small amount of carbohydrates in the evening. It’s totally fine to drink coffee or pop some caffeine if you need it to stay alert. The old trick I’ve used since the 90’s is a cup of coffee with some fats in it, preferable coconut oil, grass-fed butter and/or MCT-oil – even high fat cream is ok in small quantities. By consuming only fats, you will trick your body into a semi-fasted state and since there’s no protein, autophagy will kick in. Then have some carbohydrates later in the day. This will help you sleep better and it will “fuel you up” for the next day. Just make sure that you keep your total protein intake at less than 25 grams, preferable 15 grams. And make sure to count all the “trace amounts” of proteins and check the nutritional values of food per 100 grams; as a lot of companies will print labels based on serving sizes and if the protein per serving is less than 1 gram (even 0.9 gram), they will round it off to 0 grams.

Also, use low protein days or low protein intermittent fasting days on one of your rest days. If you’re cutting body fat, it’s ideal to implement this the day after a metabolic high calorie day or cheat day. Since you need to stimulate leptin production, you will need days where you consume more calories. Some people enjoy a half a day or even a full day of cheat meals. Following such a cheat day with a low-protein and low-calorie day will work as “damage control”, while at the same time hinder protein habituation and clean your cells trough autophagy. That’s the way I’ve done it with my clients during the last 10 years or so.

If you’re trying to gain mass, this low-protein and low-calorie protocol is even more important and effective. When you’re trying to gain muscle, you’re constantly in a calorie surplus and your protein intake is high. That’s a lot of metabolic stress on your system, especially your digestive system.
Implementing a short fast and/or restricting protein to below 25 grams will give your digestive system a break, it will lower inflammation (which is avoidable on a high calorie diet with a lot of heavy training), and it will make your cells work better through autophagy. As an added bonus, your mTOR and protein synthesis will sky rocket for a short while once you start consuming proteins again. There’s simply no reason not to implement this strategy.

What to eat

For fats, the ideal sources are MCT-oil (wonderful for energy and to fight brain fog), virgin coconut oil (also contain a bit of MCTs), grass-fed butter, tallow, heavy cream, egg yolks (very few, contains protein), avocado oil/avocados, fish oil/omega-3’s, ghee or any kind of clarified butter.

For carbohydrate sources, stick with raspberries, blueberries, pineapple, strawberries, blackberries, tangerine, grapefruit, butternut squash, sweet potato, yam, white rice, potatoes, rice cakes, and white bread. Be aware that berries and fruit contain defense chemicals, antinutrients, and trace amounts of pesticides and that they are genetically modified.

While white rice and white bread are void of nutrition, it does not matter, since all plant foods are extremely low in vitamins and minerals since they are not bioavailable and also tied to fiber and antinutrients. The more refined sources such as white rice and white bread have had most of these removed, giving you a more refined source of carbohydrates without the poison.

Also, be careful with MCT-oil/fats if you have never consumed them before, as they can upset your stomach if you take too much. Start with a teaspoon in the morning or early noon, and work up to two or three teaspoons. As MCT-oil are the perfect brain fuel, it’s best taken in the morning and at noon/early afternoon. And small portions of fat will not break your fast, so you can use MCT or coconut oil during intermittent fasting (many of my clients do).

And never, ever use a microwave for preparing or defrosting food, ever! It’s just as destructive as broiling, barbequing, stir fry or overcooking/burning food.

After following a low protein or low protein intermittent fasting day, most people feel lighter, more mentally sharp and focused, and get even better workouts. So, start to implement this strategy and let me know how you feel afterwards.

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